The present invention relates to a region extraction method for extracting a required region from an image signal, and an information processing apparatus.
Recent copying machines have many intelligent functions, i.e., functions of laying out a plurality of original images on a single sheet, copying images on the two surfaces of a sheet, and the like. Furthermore, owing to perfection of an ADF (Auto Document Feeder), documents can be automatically processed at higher speed. Especially, to copy a plurality of original images on a single recording sheet in a given layout, it is important to automatically discriminate the directions of images. For example, when the user wants to output two each of 20 original images on a single recording sheet in a given layout, i.e., to obtain 10 copies using the ADF, he or she need not adjust all the originals to their natural directions as long as the directions of original images can be automatically discriminated.
In a copying machine that discriminates the direction of an input original in this way, a character region is extracted from the read original image, and is subjected to OCR processing to discriminate its direction. In general, in order to extract a required region from an image signal, the image signal is stored in a memory directly (as a multi-valued signal) or after it is converted into a binary signal, and is subjected to signal processing such as filtering and the like or processing such as edge tracking and the like on the memory, thus extracting a required region, and separating and analyzing regions.
However, the above-mentioned method poses the following problems.
First, a memory for storing the entire image signal is required for region extraction. Although image data is converted into binary data for the purpose of region extraction, a large-capacity memory is required to store the entire image data. In this manner, the large-capacity memory dedicated to only region extraction disturbs cost and size reductions of the apparatus.
Second, region extraction cannot be started before the entire image signal is stored, thus producing a processing time delay.